
class Animal {
    hand = true;
    eat = function () {
        console.log('eat somthing')
    }
}

class People extends Animal {
    say = function () {
        console.log('say somthing')
    }
}

var cat = new Animal()
console.log(cat.__proto__ === Animal.prototype)   // true
console.log(cat.__proto__.__proto__  === Object.prototype)   // true
console.log(cat.__proto__.__proto__.__proto__)   // null

console.log('----------------')
var ssc = new People()

console.log(ssc.__proto__ === People.prototype)   // true
console.log(ssc.__proto__.__proto__ === Animal.prototype)   // true
console.log(ssc.__proto__.__proto__.__proto__  === Object.prototype)   // true
console.log(ssc.__proto__.__proto__.__proto__.__proto__)   // null